Did the Washington Redskins and Dallas Cowboys point blank tell an NFL arbitrator that the league engaged in collusion two years ago?

That is the contention of the union in legal filings last week, contradicting the NFL’s previous assertion that there was no collusion in 2010. The union has filed a collusion claim for billions of dollars in Minnesota federal court and asked the judge to reopen the legal settlement that previously governed labor relations between the two parties.

“The NFL’s [attempt] to convince the Court that there was no collusive agreement in 2010 to hold down player salaries is not only contradicted by a series of unequivocal public statements by multiple NFL Owners,” the NFLPA wrote in the legal papers, “but also by admissions from NFL teams contained in materials previously unavailable to the Court — including CBA arbitration submissions by counsel for the Redskins and Cowboys.

“In CBA arbitration proceedings, counsel for the Redskins and Cowboys made numerous statements regarding the NFL’s intention to punish those teams for failing to comply with an illegal conspiracy to restrain player spending in 2010,” the NFLPA maintained.

The Cowboys declined comment and the Redskins referred comment to the league.

“We are not commenting on the merits or on who said what to whom,” NFL spokesman Greg Aiello said.

The case stems from the NFL’s disclosure in March that it would dock the Redskins and Cowboys salary cap space because they front-loaded player contracts in 2010, a season without a salary cap. The teams objected to the penalties and their case went to an arbitrator, who sided with the league.

The NFLPA alleges it was unaware of the reason behind the cap penalties, even though the union signed off on them in order to get a higher cap number for 2012.

The NFL has pointed out that 23 teams spent more than the $123 million alleged secret cap in 2010. The league also contends that the union cannot bring the claim because it waived all rights to file it through language in the new CBA and the dismissal of the old legal settlement.

The union contends that the judge overseeing the case never signed off on that language, and the league never moved for him to do so. The sides are awaiting a decision from Judge David Doty on whether the case can go forward.

The union also threw one other tidbit into the mix in its filing last week, saying a high-profile owner directly emailed NFLPA Executive Director DeMaurice Smith in March confirming collusion.

The union in the legal papers described the correspondence this way: “A March 13, 2012 email from a prominent Owner to the Executive Director of the NFLPA shortly after the imposition of the penalties on the Redskins and Cowboys, in which the Owner — in an effort to justify those severe penalties — expressly refers to those teams’ significant expenditures ‘over a 123m salary cap’ during uncapped 2010 in comparison to teams that ‘abided by a 123m salary cap’ during uncapped 2010.”

Doty sealed many of the records tied to the Redskins and Cowboys arbitration, so all that is publicly available is what is in the NFLPA filing.